Mold for artificial teeth.



No. 669,665. Patented Mar. l2, mm. B. nusmsnu.

MOLD FOB ARTIFICIAL TEETH.

(Application filed Dec. 24, 1900.)

BERNARD RUBINSON, OF PHILADELPHIA, PENNSYLVANIA.

MOLD FOR ARTIFICIAL TEETH.

SPECIFICATION forming part of Letters Patent No. 669,665, dated March 12, 1901..

Application filed December 24,1900. Serial No. 40,894. -\No model.)

To whom it may concern:

Be it known that I, BERNARD RUBINSON, of Philadelphia, in the county of Philadelphia and State of Pennsylvania,have invented new and useful Improvements in Molds for Artificial Teeth; and I do hereby declare the following to be a full, clear, and exact description of said invention, reference being had to the accompanying drawings, and to the letters of reference marked thereon,which form a part of this specification.

This invention relates to the molds used for shaping the porcelain prior to the baking thereof for forming artificial teeth, and has particular reference to that type in which a post or a plurality of posts project from the bottom of the mold-cavity, the upper ends of the posts being shouldered to support a piece of platinumor other suitable material, so that the latter will be embedded in the tooth in position to have soldered thereto the inner end of the pin that connects the vulcanite plate to the tooth. Such molds as have heretofore been employed for this purpose have the upright projecting post or posts secured in the bottom part of the mold, and hence the posts are rigid or immovable. Such construction has been found to be objectionable for several reasons, among which are the following: The posts are usually in pairs, and if not exactly parallel with each other it is frequently difficult to perform the operation known as f delivering the teeth that is, removing or discharging them from the cavities of the mold-and even when the posts are exactly parallel they form a surface additional to the interior of the mold to which the porcelain adheres. It frequently happens therefore that the molded teeth are broken or cracked in delivering them from the mold.

The object of this invention is to retain the utility of the posts and still enable the teeth to be as readily delivered as though the posts were not present. I attain this object by providing movable instead of fixed posts and means whereby they are temporarily held in proper position during the -molding operation. Said means are, however, capable of being manipulated to permit the posts to be moved in the direction of their length, so as to withdraw them from the molded teeth prior to the discharge or delivery of the latter from the mold.

To these ends the invention consists in the construction and combination of parts, substantially as hereinafter described and claimed.

Figure 1 represents a face view of a portion of the lower member of a mold embodying my invention, the particular form of mold here chosen forillustrating the invention being one employed for forming single teeth; but it is obvious that the invention may be embodied in other forms of molds,such as those in which the cavities are arranged to form a plurality of joined teeth. Fig. 2 is a bottom plan view of the mold represented in Fig. 1. Fig. 3 represents a section on line 3 3 of Fig. 2, on an enlarged scale, and showing also a portion of the upper or complemental member of the mold. Fig. 4 represents a detail section at a right angle to the plane of Fig. 3. Fig. 5 represents a bottom plan similar to Fig. 2, but representing a modification hereinafter described. Fig. 6 represents a perspective view of one of the posts on a larger scale than in Figs. 3 and 4. Fig. 7 represents a section similar to Fig. 3, but illustrating a modification hereinafter described.

In the accompanying drawings similar letters indicate similar parts throughout the several views.

The top member of the mold is represented at a, and 1) indicates the bottom member of the mold, the two being formed with complemental recesses to form tooth-molding cavities c and the two members having means whereby they will accurately register with each other. Said means may comprise holes at the ends of the molds, as indicatedin Figs.

1 and 2, said holes being adapted to receive suitable pins.

The posts d are shouldered at their upper ends to support the pieces of platinum or other suitable material which is to be embedded in the teeth. As indicated in the drawings, the posts are formed with reduced upper ends 6, adapted to enter suitable openings formed in small pieces of platinum in a manner such as indicated in Fig. 3 of the patent to Page and Bloom, No.613,711, granted November,8,1898. This invention, however, is not limited in any way to the particular shape of the post or to the particular type of platinum anchorage employed.

Each post (1, as shown in the drawings, is fitted to slide in an openingf, which extends from the bottom of the tooth-forming cavity through to the lower face of the bottom member b. Said opening is formed with a shoulder 9, and the post is formed with a lower head or enlargement h, one side of which is other at their lower ends, as shown in Fig. 4,-

and forming the spring j large enough to not only surround one post, but also to overlap the enlargement h of the companion post of the pair.

To hold or retain the posts in the position represented in the drawings, so as to support to) in, proper position in the cavities 0, various devices may be employed. As indicated in Figs. 1, 2, 3, and 4, a locking-strip k is fitted to a dovetailed groove in the bottom of the bottom member I), so as to close the lower ends of all of aseries of openings f. Obviously, however, a separate locking-strip or its equivalent might be employed for each opening. As represented in Fig. 5, the locking-strips k extend across the bottom of the mold from side to side instead of from end to end. To prevent the posts from being ejected by the springs j or from being otherwise removed from the openings when the locking-strips are withdrawn, I may employ a pin, such as represented at m, which pin is adapted to be slid to and from the position shown in Figs. 3 and 4. Said pin fits against the flat side 2' and coacts with the shoulder at the upper end of said flat side to prevent the post from escaping from the openingf when the locking-strip is Withdrawn.

In operation the parts are in the position represented in Figs. 1 to 4, inclusive. The anchors or pieces of platinum or other suitable material, are placed on the upper ends e of the posts, the-cavities are filled with tooth material and the molding proceeds in the usual way. When the molding operation is complete and it is desired to deliver the molded teeth, the locking-strips k are withdrawn, and the springsj then act upon the posts to move them downward as far as permitted by the stop-pins m. This removes the upper ends of the posts from the molding cavities and leaves the teeth as free to be delivered as though no posts were employed.

Instead of employing springs or other means directly acting to withdraw the upper ends ofthe posts I may form the device as indicated in Fig. 7, in which the posts are shown as cylindrical and fitting cylindrical openings in the mold, the bottom face of the mold-block being formed with a recess n and the post being formed of a length so that its lower end will be flush with the lower surface of the mold block or member I) when in the position to support the anchor. With this form the workman will perform the molding operationwhile said mold is resting upon a flat top surface, so that said surface willsupport the post in the position shown in Fig. 7. Then when the molding operation is completed and the mold is lifted from its supporting surface or bed the lower end of the post may be grasped by means of pliers or other suitable tool and positively moved, so as to withdraw the upper end of the post from the cavity.

Having now described the invention and pointed out some of the forms in which it may be embodied, though without attempt- 7 .ing to describe all of such forms, I declare .that what I claim isthe platinum anchors (hereinbefore referred 1. A mold for artificial teeth havingapost movably connected therewith and having one ,end thereof adapted to project into or to be withdrawn from the molding-cavity before taking the mold apart the said end of the post being shouldered to support a piece of platinum within said cavity. 7

2. A mold for artificial teeth having an opening communicating with the cavity of the mold and extending entirely through the body thereof, and a post in said opening and movable in the direction of its length, and

.having its upper end shouldered to support a piece of platinum within said cavity.

3. A mold for artificial teeth having an opening communicating with the cavity of the mold and extending entirely through the body thereof,a post in said opening and movable in the direction of its length and having its upper end shouldered to support a piece of platinum within said cavity, and means carried by the mold for retaining the post firmly in position with its upper end projecting into the cavity.

4. A mold for artificial teeth having an opening communicating with the cavity of the mold and extending entirely through the body thereof, a post in said opening and movable in the direction of its length, and aspriug for moving said post to withdraw the upper end of the latter from the cavity.

5. A mold for artificial teeth having a pair of posts. suitably mounted therein soas to be moved in the direction of theirlength and having their upper ends adapted to project into In testimony whereof I aflix my signature the mo1ding-eavity, and a spring surronndin presence of two Witnesses. ing one of the posts and extending over a portion of the other post, whereby both posts BERNARD RUBINSON' 5 may be acted upon by the spring to withdraw Witnesses:

the upper ends of the posts from the cavity SAMUEL S. BLOOM, while the teeth are in their position. JAMES G. ATTRIDGE. 

